Now, as a genuine practitioner of compassion and Bodhicitta, you must develop tolerance. And in order to practice sincerely and to develop patience, you need someone who willfully hurts you. Thus, these people give us real opportunities to practice these things. They are testing our inner strength in a way that even our guru cannot. Even the Buddha possesses no such potential [unless he manifests them as wrathful skilful means]. Therefore, the enemy is the only one who gives us this golden opportunity. This is a remarkable conclusion, isn’t it! By thinking along these lines and using these reasons, you will eventually develop a kind of extraordinary respect towards your enemies.
— The Dalai Lama (The World of Tibetan Buddhism)
It is good if we can consider someone who hurt us as helping to “train” our tolerance and patience (enemy’s gift). It is better if we can realise that it is delusions that cause our enemies to want to hurt us. There are no physical enemies in this world who choose to hurt us. Our real enemies are greed, anger and delusions. 世上没有我恨的人，只有我恨的贪嗔痴。
But to hate (or be angry at) hatred perpetuates hatred too. We should simply recognise our greed, anger (hatred) and delusion and transform them with generosity, loving-kindness and wisdom respectively.
Well said. I hope I can do that in future. At this stage, I only managed to transfer my hatred towards people who hurt me to the 3 poisons, which are the real culprits and real enemies of all human beings. The 3 poisons caused human beings to hurt one another, and the sad thing is that most of the time, human beings are not even aware of it.
It is not always true that your own delusions cause an enemy to hurt you. Sometimes there is simply a perpetrator-victim dynamic at work. To make the recipient of harm the ultimate cause of the harm is a delusion itself, as the “just world hypothesis” has shown (google it). So the first step to overcoming an enemy is often to stop blaming yourself. And whatever anger you feel, let it be present, but use it mindfully to find safe ways to change the situation.